다공형상이 존재하는 가압기의 피로수명평가 및 응력분류선 유효성 분석

The present research deals with stress analyses and fatigue life evaluation of a new complex pressurizer that includes perforated parts due to various piping and subcomponents. At first, preliminary two- and three-dimensional finite element analyses were carried out to assess the feasibility of an effective elastic modulus. Then, the appropriateness of stress classification line prescribed in ASME Sec. Ⅲ & Ⅷ and WRC Bulletin 429 as non-mandatory appendices was reviewed. Finally, after categorizing stress components, the stress intensities and cumulative usage factors at critical points of pressurizer were calculated through main analyses and compared with corresponding allowable design criteria in ASME code.